Home
/
Physics
/
14. What Is the Velocity of the "8"ball After the Elastic Collision Below?

Question

14. What is the velocity of the "8"ball after the elastic collision below?

Answer

4 (244 Votes)
Verificación de expertos
Lionel Professional · Tutor for 6 years

Answer

To solve this problem, we will use the conservation of momentum and the conservation of kinetic energy, which are both applicable in an elastic collision.The conservation of momentum states that the total momentum before the collision is equal to the total momentum after the collision. The conservation of kinetic energy states that the total kinetic energy before the collision is equal to the total kinetic energy after the collision.Let's denote:- as the mass of the moving ball (0.25 kg)- as the initial velocity of the moving ball (2.0 m/s)- as the final velocity of the moving ball (0.1 m/s)- as the mass of the "8" ball (since it's a standard pool ball, it should also be 0.25 kg)- as the initial velocity of the "8" ball (0 m/s, since it's not specified, we assume it's at rest)- as the final velocity of the "8" ball (which we are trying to find)Step 1: Apply conservation of momentumThe total initial momentum is the sum of the momentum of both balls before the collision: The total final momentum is the sum of the momentum of both balls after the collision: Since momentum is conserved: Step 2: Substitute the known values and solve for Step 3: Apply conservation of kinetic energy (to confirm the collision is elastic)The total initial kinetic energy is: The total final kinetic energy is: Since kinetic energy is conserved: The kinetic energy is not exactly conserved according to these calculations, which suggests that either the collision is not perfectly elastic or there is a rounding error in the calculation. However, since the question asks for the velocity of the "8" ball after an elastic collision, we will proceed with the assumption that the collision is elastic and that any discrepancy is due to rounding.Final Answer:The velocity of the "8" ball after the elastic collision is approximately 1.9 m/s.